This invention relates to sump pumps and in particular to a water-powered sump pump.
Sump pumps are normally electrically powered utilizing water level sensors to activate electric motor driven pumps. Because sump pumps are most frequently called upon during and immediately after storms, electric service may not be available throughout the time period in which the pump is required to act. While it has been known to provide battery backup systems to supply electric power during power outages, such backup systems are quickly drawn down, are difficult to maintain at optimum charge and require periodic replacement of the batteries.
It has been proposed to utilize water-powered pumping systems where a connection to a water supply, such as a municipal water system, may be available to provide an uninterrupted pressured flow even during times of electrical outage. Such devices may include venturi devices or turbine vane pumps.
While such devices may work during periods of electrical outage, they are relatively inefficient, having small pumping capacities in comparison to the volumes of water required, may have small operating heads, and provide back flow contamination problems, particularly in those situations, such as venturi devices, where the high-pressure water, generally potable water, mixes directly with the gray water from the sump.
It therefore would be an advance in the art to provide a non-electrically driven sump pump having relatively higher efficiencies than current water-powered sump pumps.
It would be a further advance in the art to provide a relatively high efficiency water-powered positive displacement sump pump which avoids back flow problems.
It would be a further advance in the art to provide a water-powered sump pump utilizing a reciprocating positive displacement pump having a pumping chamber submerged in the sump with a drive chamber connected to a pressure water supply, the drive chamber spaced from the pumping chamber and employing a reversing valve to reciprocate the positive displacement pump.
These and other advantages and features of the invention are provided by my design which incorporates a positive displacement pump including a pump chamber received in the sump having an intake open to the sump and a discharge to waste which employs a reciprocating driving member driven by a mechanical connection to a drive or power chamber which in turn has a reciprocating member acted upon by pressure water to reciprocate the driving member, the pressure water being controlled by a reversing valve.
In one embodiment of the invention, the pump chamber, positioned adjacent to the bottom of the sump is provided with a reciprocating member such as a piston or a diaphragm which is linked by a piston rod to a reciprocating driving member, such as a piston or diaphragm, in a power cylinder spaced above the bottom of the sump. A flow-reversing valve alternately directs pressure water from a pressure water supply to one side or the other of the reciprocating member in the power cylinder thereby reciprocating the diaphragm or piston in the power cylinder. The volume of the power cylinder traversed by the driving member is a fraction of the volume of the pumping chamber traversed by the pumping member such that for an equal stroke length, a smaller volume of water in the pumping chamber at a higher pressure moves a larger volume of water in the pumping chamber at a lower pressure. Since normal line pressure from a municipal water system generally exceeds 25 psi (and may be in the range of 30-60 psi), and since the normal pump head from a sump to a discharge line, over the top of a building foundation to a storm sewer, is only on the order of five to twelve feet, volumetric pumping capacity on the order of three to five times greater are easily obtained. Such efficiencies permit the discharge from the pumping chamber to be drawn in with the gray water from the sump while still maintaining good pumping efficiency. By providing an air gap between the discharge of the power chamber and the high water level of the sump, the potable water system is effectively separated from the gray water and back flow cannot occur.
A standard float switch can be utilized to control an on/off valve for providing pressure water to the reversing valve and appropriate check valves may be provided to control intake and discharge from the pumping chamber.
In a further embodiment of this invention, the drive chamber can be positioned above the top of the sump with either a discharge directly to waste, preferably while maintaining an air gap, or with discharge directly to the sump.
It is therefore one object of this invention to provide a positive displacement, pressure water, sump pump having separated drive and pumping modules wherein the drive module includes a drive chamber having a reciprocating power member driven by pressure water through a reversing valve, the reciprocating power member being mechanically linked to a reciprocating pump member received in a pump chamber located adjacent to the bottom of a sump, with the pump chamber having inlets open to the sump and outlets open to discharge and where reciprocation of the reciprocating power member encompasses a volume less than the volume encompassed by reciprocation of the pumping member.
Other features of this invention will be apparent to those of ordinary skill in the art from the following description of a preferred embodiment, it being understood that those skilled in the art will appreciate that the preferred embodiments described may be easily modified with respect to most details thereof while maintaining the advantages of this invention.